A conventional image sensor module generally comprises an image sensor chip, a substrate for mounting the chip, and a housing installed on this substrate. The image sensor module further comprises a lens for focusing light from an object onto the image sensor chip for image formation. This lens is retained at a predetermined position in the housing.
In order to obtain a clear image, the lens must be accurately installed with respect to the image sensor chip. However, a conventional image sensor module does not have a simple structure which enables accurate installation of a lens. Therefore, in some cases a clear image cannot be obtained due to an inappropriate mounting position of the lens. Further, the manufacturing cost of the image sensor module is high because the mounting structure of the lens is complicated.